Some launch capsules carry payloads that are intended to be separated from the capsule in flight. This familiar process of deploying munitions or the like from a capsule is depicted in FIGS. 1A through 1C.
FIG. 1A depicts the launch of capsule 100. In this illustration, capsule 100 contains booster 108, which provides the thrust required for launch. In this example, the payload is an unmanned aerial vehicle, usually referred to as a “UAV.” The UAV is not visible in FIG. 1A since it is within shell 102
At some predetermined altitude or time, shell 102 of capsule 100 opens in preparation for releasing UAV 110, as depicted in FIG. 1B. Typically, explosive bolts or similar mechanisms are used to open the capsule. As the capsule opens, UAV 110 is released from launch restraints so that it is free to separate from the capsule. The release mechanism can be, for example, explosive bolts or the like.
Aerodynamic forces assist with the continued opening of capsule 100 and deployment of UAV 110. More particularly, once capsule 100 partially opens, air resistance forces segments 104 and 106 of shell 102 further apart. The force of the air against segments 104 and 106 also slows capsule 100. Since UAV 110 has been released from its restraints so that it's no longer coupled to the capsule, its forward motion is not retarded at the same rate as capsule 100. As a consequence, UAV 110 separates from the capsule, as depicted in FIG. 1C.
There are several important considerations regarding capsule-deployed payloads. One consideration is that the payload must be able to withstand the axial shock of the capsule's launch. To that end, the launch capsule typically incorporates a shock isolation system that substantially isolates the payload from axially-aligned shock (e.g., due to the high rate of acceleration that is required for launch).
A second consideration relates to the specifics of payload deployment. For some applications, the success of the deployment operation will depend upon how quickly the payload separates from the capsule. In this regard, one concern relates to the presence of debris, which is often produced when the capsule opens. This debris can damage the payload. A second concern applies to payloads that deploy wings to sustain flight. If the payload doesn't rapidly clear the capsule, the wings can be damaged during deployment.
Payload separation can be particularly problematic during low-speed deployments, wherein relatively diminished aerodynamic forces are available to brake the capsule. In such cases, the payload and capsule might not separate enough to permit safe wing deployment or for the payload to clear debris, etc.
There is a need, therefore, for a way to reduce the risks to payloads that are deployed from launch capsules.